KRAS Mutations in Lung Adenocarcinoma: Molecular and Epidemiological Characteristics, Methods for Detection, and Therapeutic Strategy Perspectives

KRAS mutations are detected in over one third of lung adenocarcinomas, most frequently in Caucasian and smoker patients. The impact of KRAS mutations on lung adenocarcinoma prognosis is currently subject to debate, as is their impact on the response to chemotherapy and EGFR tyrosine kinase inhibitors. The different methods for KRAS status assessment, based on histological and cytological samples or biological fluids, offer varying sensitivities. Since no treatments are available in clinical routine for KRAS-mutated lung cancer patients, one of the current major challenges in thoracic oncology is developing new dedicated strategic therapies. Different molecules can be developed that act on a post-transcriptional KRAS protein level, blocking its cytoplasmic membrane recruitment. The efficacy of these molecules' targeting of the different signaling pathways activated by the KRAS mutation (such as the MEK and BRAF pathways) is related to the particular KRAS mutation subtype. New therapeutic strategies are currently focused on certain genes linked with KRAS inducing a synthetic lethal interaction. The purpose of this work is to provide an overview of i) the recent epidemiological and molecular findings concerning KRAS-mutated lung adenocarcinoma, ii) the prognostic impact of KRAS mutations, in particular during response to treatment, iii) the available methods for detecting this mutation, and iv) the current molecules under development for new therapeutic strategies and the clinical trials targeting this genomic alteration.